Introduction

In this article, we will learn how to disable the new window/tab in web applications. There are two challenges in preventing multiple windows or tab usage in web applications: i.e how can we differentiate among two requests (GET or POST) at the server-side and how we can stop the user from generating a request (GET or POST) from two tabbed/different windows at the client-side.
The solution to the above problems is the use of window.name at the client-side using JavaScript and checking the HTTP Referer header at the server-side.
Step 1: First we create a Homepage.aspx in our website, like this:
  1. <head runat="server">
  2. <title>Home - Restrict Multiple Tab</title>
  3. <script language="javascript" type="text/javascript">
  4. if(window.name != "<%=GetWindowName()%>")
  5. {
  6. window.name = "invalidAccess";
  7. window.open("InvalidAccess.aspx", "_self");
  8. }
  9. </script>
  10. </head>
  11. <body>
  12. <form id="form1" runat="server">
  13. <div>
  14. <h2>Try to Open the Link given below either in new window or tab.</h2><br />
  15. <img src="image/img1.jpg" alt="Image" align="right" />
  16. <br />
  17. <asp:HyperLink ID="hlDemo1" runat="server" NavigateUrl="~/Demo1.aspx">Page 1</asp:HyperLink>
  18. <asp:HyperLink ID="hlDemo2" runat="server" NavigateUrl="~/Demo2.aspx">Page 2</asp:HyperLink>
  20. <asp:HyperLink ID="hlDemo3" runat="server" NavigateUrl="~/Demo3.aspx">Page 3</asp:HyperLink>
  21. </div>
  22. </form>
The output of this page looks like this
Clipboard01.jpg
Step 2: Now create a Demo1.aspx page:
  1. <head runat="server">
  2. <title>Demo 1</title>
  3. <script language="javascript" type="text/javascript">
  4. if(window.name != "<%=GetWindowName()%>")
  5. {
  6. window.name = "invalidAccess";
  7. window.open("InvalidAccess.aspx", "_self");
  8. }
  9. </script>
  10. </head>
  11. <body bgcolor="green">
  12. <form id="form1" runat="server" >
  13. <div>
  14. <h1> Page 1 </h1>
  15. Try to Open the Link given below either in new window or tab.<br />
  16. <img src="image/img.jpg" alt="Image" align="right" />
  17. <br />
  18. <asp:HyperLink ID="hlDemo1" runat="server" NavigateUrl="~/Demo1.aspx">Page 1</asp:HyperLink>
  19. <asp:HyperLink ID="hlDemo2" runat="server" NavigateUrl="~/Demo2.aspx">Page 2</asp:HyperLink>
  21. <asp:HyperLink ID="hlDemo3" runat="server" NavigateUrl="~/Demo3.aspx">Page 3</asp:HyperLink>
  22. </div>
  23. </form>
The output of this page looks like this
Clipboard02.jpg
Step 3 : Now create a Demo2.aspx page
  1. <head runat="server">
  2. <title>Demo 2</title>
  3. <script language="javascript" type="text/javascript">
  4. if(window.name != "<%=GetWindowName()%>")
  5. {
  6. window.name = "invalidAccess";
  7. window.open("InvalidAccess.aspx", "_self");
  8. }
  9. </script>
  10. </head>
  11. <body bgcolor="lime">
  12. <form id="form1" runat="server">
  13. <div>
  14. <h1>Page 2</h1>
  15. Try to Open the Link given below either in new window or tab.<br />
  16. <img src="image/img.jpg" alt="Image" align="right" />
  17. <br />
  18. <asp:HyperLink ID="hlDemo1" runat="server" NavigateUrl="~/Demo1.aspx">Page 1</asp:HyperLink>
  19. <asp:HyperLink ID="hlDemo2" runat="server" NavigateUrl="~/Demo2.aspx">Page 2</asp:HyperLink>
  21. <asp:HyperLink ID="hlDemo3" runat="server" NavigateUrl="~/Demo3.aspx">Page 3</asp:HyperLink>
  22. </div>
  23. </form>
  24. </body>
The output of this page looks like this
Clipboard03.jpg
Step 4 : Now create a Demo3.aspx page
  1. <html xmlns="http://www.w3.org/1999/xhtml" >
  2. <head runat="server">
  3. <title>Demo 3</title>
  4. <script language="javascript" type="text/javascript">
  5. if(window.name != "<%=GetWindowName()%>")
  6. {
  7. window.name = "invalidAccess";
  8. window.open("InvalidAccess.aspx", "_self");
  9. }
  10. </script>
  11. </head>
  12. <body bgcolor="#669999">
  13. <form id="form1" runat="server">
  14. <div>
  15. <h1>Page 3</h1>
  16. Try to Open the Link given below either in new window or tab.<br />
  17. <img src="image/img.jpg" alt="Image" align="right" />
  18. <br />
  19. <asp:HyperLink ID="hlDemo1" runat="server" NavigateUrl="~/Demo1.aspx">Page 1</asp:HyperLink>
  20. <asp:HyperLink ID="hlDemo2" runat="server" NavigateUrl="~/Demo2.aspx">Page 2</asp:HyperLink>
  22. <asp:HyperLink ID="hlDemo3" runat="server" NavigateUrl="~/Demo3.aspx">Page 3</asp:HyperLink>
  23. </div>
  24. </form>
  25. </body>
The output of this page looks like this
Clipboard04.jpg
Step 5: Create a Default.aspx page where we use window.name at the client-side using JavaScript. On page load, the following script will execute:
  1. <head runat="server">
  2. <title>Default</title>
  3. <script language="javascript" type="text/javascript">
  4. if (window.name == "default") {
  5. var windowFeatures = 'channelmode=0, directories=0, location=0, menubar=0, resizable=0, scrollbars=1,status=1,titlebar=0,toolbar=0,top=0,left=0,width=800,height=600';
  6. //With windowFeatures
  7. window.open("Home.aspx", "<%=GetWindowName()%>", windowFeatures);
  8. window.opener = top;
  9. window.close();
  10. }
  11. else if (window.name == "") {
  12. window.name = "default";
  13. window.open("Default.aspx", "_self");
  14. }
  15. else if (window.name == "invalidAccess") {
  16. alert("Invalid access. Please close the window, and try again.");
  17. window.close();
  18. }
  19. else {
  20. window.name = "invalidAccess";
  21. window.open("Default.aspx", "_self");
  22. }
  23. </script>
  24. </head>
  25. <body>
  26. <form id="form1" runat="server">
  27. <div>
  28. </div>
  29. </form>
Step 6: Then we create an InvalidAccess.aspx page which is used only when the user opens a page either in a new window or a tab:
  1. <head runat="server">
  2. <title>Invalid Access</title>
  3. </head>
  4. <body>
  5. <form id="form1" runat="server">
  6. <div>
  7. <h1> Invalid Access. Please close the window and try again.</h1> <br />
  8. </div>
  9. </form>
  10. </body>
  11. <script language="javascript" type="text/javascript">
  12. alert(" Operation not allowed either you opened this webpage in a new tab or a new window. ");
  13. window.close();
  14. </script>
The output of this page looks like this:
Clipboard06.jpg
The final result when the user tries to open a new window/tab looks like this:
Clipboard20